I got out my 817 after period of inactivity. I went to check the swr using the 817. I am getting some strange results. At first I got no bars. I tried later, and got several bars. Then I got 2 bars. What is going on?

A comeback problem after long inactivity can usually be caused by crudded up connectors, switches and controls, relay contacts and or antenna problems.

In order to suggest a logical plan for correcting your problem I would like to know if you have a dummy load and an SWR meter?

If you have neither, then you could "shotgun" it and get a can of contact cleaner (this in itself requires some research and investigation to avoid buying a product that disolves plastics, etc.) and start with the switches and controls in the radio. If the radio has an antenna changeover relay then the contacts could be cleaned with a piece of paper pulled between the contacts while pushing on the relay arm.

Don't forget to clean the SO-239 or BNC antenna connector, whichever it has.

If it's and antenna problem, then an SWR meter is necessary to confirm this.

I am using a Miracle Ducker TL connected directly to rear antenna on my ft-817nd. I do not have a dummy load or swr meter. I do have a MFJ antenna analyzer. Sounds like I might need to adjust the antenna per instructions and then remove and attach it to the antenna analyzer.

I have quite a lot of experience with the Miracle Whip / Ducker. One thing comes to my mind immediately.

Are you using a counterpoise wire? Or anything that would act as an counterpoise wire (for example, power supply cable and an external power supply)?

Without a counterpoise wire, the SWR will depend very much on any other object attached / close to the radio. Your hand, the mic cable, etc. - anything attached to the radio is now the counterpoise. The same applies if you place your hand close to the Miracle Ducker tuning knob or not. Do a simple test. Adjust the SWR to the lowest number while holding the knob, and then move your hand away. I bet the SWR will change by a couple of "bars". It's less of a problem on shorter bands (10 and 15 m), but absolutely critical on longer bands (20, 30 and 40 m, the Miracle Ducker is pretty much useless beyond 40 m).

The Miracle Ducker is essentially a short vertical radiator and it MUST have a counterpoise / ground plane to work properly. Without it, it's completely unpredictable.

The only way to cure this problem is to ground you radio or provide appropriate counterpoise wire.

I don't think a ring around the BNC connector will provide reliable connection. This could actually explain the wild changes in SWR. Try connecting the counterpoise wire to the radio grounding screw in the back, just under the rear antenna connector.Another issue may be misaligned connection inside the Miracle Ducker tuner itself. If the sliding arms is not perfectly aligned, it sometimes touches two adjacent pads at the same time, causing swings in SWR.S. BuckiKD8KQH

I wouldn't worry too much about the results you're seeing. It's not like you'll be making contacts with that setup anyway. The only thing you'll be working is your next door neighbor's PC speakers with a miracle whip antenna on a QRP rig inside of an apartment. Seriously - I wouldn't waste my time with an antenna like that. QRP indoors is a challenge enough without piling a minus 20dB antenna on it.

Unless you have a metal floor in a wooden house or something, I'd avoid an indoor vertical. Could it be that the antenna is severely detuned by nearby objects or something? (Like house wiring, metal siding, etc.)

You can still make contacts on CW and PSK-31 on something like that, if you get it to match, but if you want to have a better indoor antenna, get a dipole up in the attic or even a wooden ceiling. I've been lucky enough to even work SSB DX on my FT-817 on ceiling dipoles.

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